Less obscure behaviour while copying the assets

[lorenzosinisi]

I wanted to open a pull request making the task :assets_precompile (For Rails) more explicit.

Right now if the task :assets_precompile is skipped the output says Skipping asset precompilation while what is happening is that the previous public/assets folder is copied into the new one. This is a very obscrure behaviour and outputting what is 'actually' happening will prevent confusion. What do you think?

in tasks/mina/rails.rb

66 -   skip: %{echo "-----> Skipping asset precompilation"},
66 +   skip: %{echo "-----> Skipping asset precompilation and cloning from previous assets folder."},

[d4be4st]

This is the way 0.3.x version has done.
In 1.0.0 assets are link shared and not copied.